Ribbon feeding and reversing mechanism



April 17, 1956 g, p, ANDERSON 2,742,132

RIBBON FEEDING AND REVERSING MECHANISM Filed Oct. 16, 1950 2 Sheets-Sheet 2 INVENTOR CARI. P. ANDERSON ATTORNEYS United States Patent 2,742,132 RIBBON FEEDINGAND REVERSING MECHANISM Carl PrAnderson, HighlandPark, Ili., assignor to Kleinscllmidt Laboratories, Inc., Deerfieid, 1th., a corporation of Delaware Application October 16, 1950, Serial No. 190,426

17 Claims. cl. 197-460) This invention relates to'typewriting machines and particularly to an automatic ribbon feed and reversing mechanismfor'telegraph printers in which the ribbon feed and reversing'mechanism is moved across the printed page with the printing mechanism.

In machines of this class it is desirable to provide uniformly printed impressions, and to accomplish this it is necessary that the inking or typing ribbon be uniformly used over its entire length and that provision be made for reversing the feeding movement of the ribbonwhen it has been substantially all wound on one spool.

In the printers of the prior art the ribbon feeding and reversing mechanism has generally been connected to the prime mover of the machine. This necessitates many complex" parts adding to the weight and bulk of the printer, and often making the ribbon mechanism difficult toget atfor adjustment or replacement of parts.

In the invention embodied herein the ribbon feeding and reversing mechanism is not connected to the prime mover of the printer but derives its operative movement from the character spacing movement of a movable type carriage; This novel construction eliminates most of the complex and complicated parts which operate the ribbon mechanisms in prior art machines. In addition, the ribhon mechanism of the invention may be built as a unit for r'eady'attachment to the movable carriage of any type of printer, and may be mounted so that it is readily accessible'for any necessary adjustment or replacement of the ribbon spools. The ribbon mechanism embodied herein is also pro'vided with a novel reversing arrangement which is completely automatic and yet is of simple cons'tr'uction using few parts.

With these and" other considerations in view it is a primary object of this invention to provide novel and unique means in a typewriter'of the class described for feeding the inking ribbon and for automatically reversing thefeed while the printing and associated ribbon feed mechanism is movedacros's the printed page.

Anotherobj'ect of this invention is to provide in a typewriter having a movable. type bar carriage a ribbon feeding" andreve'rsin'g mechanism which derives its operating power as an incidence of the'character spacing movement o f the type. bar carriage thereby reducing the necessary wearingpartsand decreasing the weight of the carriage;

Another object of this'invention is to'provide in a typewriter a. ribbon feeding and reversing mechanism carried on amovable carriage which-mechanism comprises a gearin'g-arra'ngeinent actuated by the spacing movement of: the carriage to o'perate the ribbon feed drive.

further object: of this invention is to provide in a ribbon feeding and revers'ingmechanism supported on a movable cai r iage a gear and clutch arrangement for feeding theribbonas the carriage is moved for character spacing Bufw'h'ich arrangement is disconnectedby theclutch when the carriage isreturned to its starting position.

Anotherobject of this invention is to provide an inking ribbon feeding and reversing device which may be constructed as a unit and quickly and easily installed on or removed from the typewriter.

Still another'object of this invention is to provide a ribbon reversing mechanism which is controlled by the available unused supply of ribbon rather than by the strain or pull exerted upon the ribbon.

For a more complete understandingof the invention reference may be had to the following detailed description taken in conjunction with the accompanying drawings, in which like reference characters in the different views repre sent like parts, and in which:

Figure l is a front elevation of the ribbon. feeding and reversing mechanism assembled as a unit structure;

Figure 2 is a frontelevation of part of the ribbon feeding mechanism mounted on a movable carriage;

Figure 3 is a plan view of part of the ribbon feeding device and movable carriage with the upper part of the spools cut away;

Figure 4 is a plan view of the gearing and clutch arrangement of the invention; and

Figure 5 is a detail elevation of the ribbon reversing cam and cam follower arrangement Ribobn feeding mechanism Referring to the drawings, and more particularlyto Figure 1, a ribbon feeding and reversing device is shown'as a unit structure in which theinking or typing; ribbon and the ribbon supply spools somewhat resemble the ribbon mechanism of most standard typewriters. Figure 2 shows the unit structure mounted upon a movable carriage of the type to bereciprocated by power means in front of a stationary platen holding a paper upon which the received telegraphic message is to be printed. As is wellknown in the art, such movable carriages are arranged to be intermittently operated as characters are printed upon the paper to properly space the printed characters andwords, and when the end of the lineis reached to be returned to thestart of the next line in one continuous operation;

Figure 2' illustrates such a movable carriage 10 supported on rollers 12 and 1 t fixed to axles respectively secured in hub extensionslo and 18 of the carriage frame 20. A rail 22 is secured to the frame of the printer in any suitable manner to coact with the rollers 12 and 14 which are arranged in pairs and engage opposite sides ofthe rail to support the weight of the movable carriage 10. Other rollers which are not shown may bear against other portions of the printer to help support and guide the carriage. A type bar segment or comb guide 24 is a part of the carriage 1t and supports and aligns the usual type bars 25 of the printer as shown in Figure 3. The ribbon feeding, and reversing mechanism is a complete unit as shown in Figure 1. It may be assembled as a unit to facilitate its attachment to and detachment from. any suitable typewriter. When in place on a machine the ribbon supply spools are located near the top and front where they are easily accessible for adjustmentor removal. The supporting members or brackets 26 and 28 of the unit are secured to the carriage frame 20' by screws 30 which engage tapped holes 31 in the frame. Brackets 26 and 28 support vertically disposed spindles 32' and 34 upon which are placed, respectively, ribbon supply spools 36 and 38 which fit in cup-shaped shields 39. Clips 40 and 42 are pivoted in the ends of the spindles 32 and 34 and serve toremovably secure 3 be seen, as is customary in many printers of the prior art.

The ends of the ribbon 46 are detachahly secured to the ribbon supply spools 36 and 38, the hub portions of which are notched at 48 to receive projections 5'0 formed on collars 52 rigidly secured to spindles 32 and 34 so that the spools 36 and 38 are respectively rotatable with the spindles 32 and 34. Spindles 32 and 34 pass all the way through the brackets 26 and 28 and are provided at their lower ends with bevel gears 54'and 56 respectively adapted to mesh, but not at the same time, with the pinion gears 58 and 60 rigidly secured to the ends of a drive shaft 62 supported in a yoke 64 secured to extensions 66 of the supporting members 26 and 28. One set or the other of these gears is always in engagement. The drive shaft 62 is rotated by a jaw clutch which has a driven member 68, Figures 1 and 4, secured to the shaft 62 in any suitable manner as by a set screw and a driving member '70 fastened to the hub portion of an helical gear 72 slidably mounted on the shaft 62 and adjustably positioned with respect to the driven member 68 by a spring 74 and a collar 76 positioned on the shaft 62 by a set screw 78. The helical gear 72 engages a spiral rack 80, Figure 2, fastened on the bottom of the rail 22. If desired, the rack 80 may be formed as an integral part of the rail.

Rack 80 has a plurality of teeth 81 formed at an angle to the longitudinal axis of the rack so that in effect, they form a spiral or helical gear which meshes with the helical gear 72 to drive shaft 62 as the carriage moves to the right for the spacing of successive characters. The movable carriage 10 may be driven by any suitable means, but is particularly adapted for use with the carriage advancing means disclosed in copending application Serial No. 769,664, filed August 20, 1947, by E. E. Kleinschmidt, now Patent No. 2,606,641, in which an electric motor is operably connected to the movable carriage to intermittently move it to the right as successive characters are printed. Each such character spacing movement causes the helical gear 72 to engage one of the teeth 81 on the rack 80 and be rotated a slight degree to turn the jaw clutch members 70 and 68 and the drive shaft 62. When gears 58 and 54 are in engagement, as shown in Figures 1 and 2, spindle 32 and ribbon supply spool 36 will be rotated to wind up part of the ribbon 46 pulling a small amount through the guide 44 each time a character is printed. During this process the other ribbon supply spool 38 idles and unwinds a like amount of the ribbon 46.

It is to be noted that the ribbon feeding mechanism is not connected to the prime mover of the telegraph printer as is customary in machines of the prior art but derives its operative movement as incidental to the character spacing movement of the moveable carriage. As mentioned hereinbefore, such an arrangement eliminates the many cumbersome and complicated parts heretofore provided in machines of the prior art to furnish power for operating the ribbon feeding mechanism.

When the carriage 10 is moved to the left to start a new line of printing, the helical gear 72 rotates in a direction opposite to that described above. Due to the lateral'friction induced on the gear 72 by the rack 80 and teeth 81 on the return movement of the carriage, and to the construction of clutch members 68 and 70, no driving action will take place but instead member 70 will slip over the teeth of member 68 and slide on shaft 62 to compress spring 74 which normally tends to keep the clutch members 68 and 70 engaged. As soon as the carriage 10 has reached the position at the start of a new line, and the backward movement of the carriage and helical gear 72 ceases, the spring 74 will force clutch member 70 into engagement with member 68 to drive the ribbon feed mechanism when the carriage again starts to the right.

Ribbon reversing mechanism When the inking ribbon 46 is wound substantially entirely on one spool the direction of feeding the ribbon is reversed automatically to rewind the ribbon on the then empty spool. The reversing mechanism is set into operation when the last turn of the ribbon is unwound from the paying-out spool by the pivoting of a sensing lever which then protrudes through a window in the spool, and is completed by a camming action which connects the driving means to the empty spool. As shown in Figure l the supply of ribbon 46 on spool 36 has just been exhausted and the mechanism has just been shifted to reverse the direction of feeding movement of the ribbon 46 by winding it upon spool 36. The core of the ribbon spool 36 has a cut-out portion or window 252, Figures 1, 2 and 3, extending partially around its circumference through which the angularly displaced end 54 of a sensing lever 86 is permitted to protrude when the last turn of the ribbon 46 has been unwound from the spool 36. So long as one turn of ribbon is on the spool the sensing lever is retained in the position shown for the right-hand sensing lever 88 associated with spool 38 in which the end 90 is held in the window 92. The end 90 has a curved back portion 91 which is shown in Figure 3. This portion 91 bears against the ribbon 46 without injuring it. The end 84 of sensing lever 86 is similarly shaped to serve corresponding purposes. The first turn of the ribbon 46 on the spool 36 will place the sensing lever 86 in the same relative position as the sensing lever 38 is shown in Figure 1. The ribbon 46 will then continue to wind on the spool 36 until the last turn of the ribbon 46 is removed from the window 92 at which time the end 90 will pass through the window 92 and the lever 88 will pivot on the post 94 under the influence of a spring 96 secured under tension between an ear 93 on the sensing lever 88 and the bracket extension 66.

Affixed to the sensing lever 88 are studs 102 which fit loosely in slots 104 formed in the legs of a substantially U-shaped portion 106 of a cam follower 108. The pivot post 94 is located between the legs of U-shaped member 106 and is so arranged with respect thereto and to the studs 102 and notches 104 that when the sensing lever 88 pivots about the post 94 this pivoted movement will be transferred to the cam follower 108 which will move to the right as viewed in Figure 1 until it is under the cam 110, Figures 1 and 5, secured to the drive shaft 62. The cam 110 is formed with two lobes 111 diametrically opposite each other so within the next half revolution of the drive shaft 62 one of the lobes will engage the cam follower 108 which will slide on the studs 102 and be moved downwardly. A pin 112 is fixed in the cam follower 108 and enters a slot 114 in a beam 116 pivoted substantially at its center on stud 118 secured in a portion of the support yoke 64. The downward movement causes the beam 116 to rock on the pivot 118 in a clockwise direction so that the beam ends 120 and 122 which respectively engage annular collars 124 and 125 slidably keyed to the vertical spindles 32 and 34 cause the gears 54 and 58 to disengage and the gears 56 and 60 to engage. The shifting of the gears disconnects the drive shaft 62 from the spindle 32 and connects it to spindle 34 whereupon the then empty spool 38 becomes the take-up spool. As soon as one layer of ribbon 46 is wound upon the spool 38 and the sensing lever end 90 is pushed back out of the window 92, the sensing lever 88 pivots to move the cam follower 108 out of the path of the cam 110 and into the position shown in Figure 1 of the drawings. Thereafter, when the last layer of ribbon 46 is unwound from spool 36 the sensing lever 86 will pivot its cam follower 126 into the path of left-hand cam 127 which will move the mechanism back into the position shown in Figure 1 to repeat the cycle.

The spindles and gears are held in the position to which they are shifted by a detent mechanism which also imparts a snap action to the movement of the beam 116 to facilitate the action. The detent mechanism consists ofa pointed latch plate 123 suitably fixed to the beam 116 anda detent 130 pivoted on a stud 132 secured inan arm 134 of the yoke 64. To the lower end of detent 130 is fastened one end of a tensioned spring 136 which has its other end fastened to a projection 138 on the yoke 64; The spring 136 is normally under suflicient tension to maintain the detent 130 against the plate 128 andprevent the unauthorized rocking of the beam 116. However, the drive shaft cams 110 and 127 in rocking the beam 116 overcome the spring 136, and the angular faces 140 on the plate 128 and 142 on the detent 130 move the detent to the left as shown inFigure lto permit the points of the detent and plate to slide past each other. The additional tension thereby placed on the spring 136 issuificient to cause a snap action of the beam 116 into its new position to assure the positive disengagement of one set of gears and the positive engagement of the other set of driving gears. The drive shaft cams 110 and 127 each have two lobes which are diametrically opposed, and the cams are so positioned on the shaft 62 that the lobes on cam 110 are at a 90 angle with respect to the lobes on cam 127 This is necessary to preventblocking or binding of the shift mechanism.

Handles 144 and 146 are formed onthe sensing levers 8'6=and 88 respectively to permit the removal of the associatedribbon'supply spool from the spindle. Depressing the handle 144, for instance, removes the end 84 from the window 82; then placing the clip 40 in its upright position willpermit the removal of the ribbon spool from the spindle. The action of the handle 146andits associated parts is similar to that just described.

From the foregoing disclosure it is readily apparent that I have provided a novel and unique ribbon feeding device which includes a typewriter carriage and rendered inoperative while the carriage is being returned tostart a new line of printing. Further, the feeding arrangement is reversed automatically when substantially all the ribbon has been unwound from one spool to cause the ribbon to be wound on the empty spool. The mechanism is simple of construction and may be built as a unit which can then be attached to the movable carriage of any printer in such a manner that the ribbon spools are easily reached for adjustment or replacement;

While I have illustrated and described a preferred embodiment of my invention, it is to be understood that the device is capable of modification and I do not wish to be limited to the precise details set forth but desire to avail myself of the scope of the invention as set forth in the following claims.

What is claimed and desired to be secured by United States Letters Patent is:

1. In a typewriter having a movable carriage, a ribbon feeding device mounted on said movable carriage comprising'a pair of rotatably mounted spools having an ink ribbon wound thereon, slidable movement receiving means connected to said spools, means for imparting movement to said spools including a rotatable driving member mounted in axially fixed relation upon said carriage and engageable with the movement receiving means of either of said spools, and a gear and clutch controlled by the movement of said carriage in a character spacing direction for operating said driving member to feed said ribbon from one of said spools to the other.

2. In a typewriter; a movable carriage; an inking ribbon; spools for said ribbon horizontally mounted on said carriage; and means for imparting movement to said spools to reversibly feed said ribbon including a spiral rack on said typewriter, an axially fixed drive shaft on said carriage to actuate either of said spools, and a spiral pivots the lever 86 and gearing arrangement operated incidentally to the character spacing. movement of the 6 gear coacting withsaidrack and sa'id shaft to actuate said shaft as said carriage is moved.

3. In a typewriter; a carriage intermittently movable in one direction and continuously movable in the other direction; an ink ribbon feeding and reversing device mounted on said carriage including a pair of rotatable spools having an ink ribbon wound thereon; and means for imparting movement to said spools to feed said ribbon, including a spiral rack on said typewriter, a drive shaft on said carriage toalternately drive said spools, a spiral gear in mesliw-ith said rack, and a positive clutch effective upon the intermittent operation of said carriage to connect said gear tosaiddriveshaft;

4; In a telegraph printer having rack means secured thereto, a movable carriage, a ribbon feeding and reversing mechanism mounted on said carriage, an axially fixed drive shaft secured to said mechanism, means on said drive shaft and coacting with said rack" means to rotate said drive shaft as said carriage moves in a character spacing direction, a pair of rotatable membersmounted on said mechanism, anink ribbon mounted on saidmembers and adapted to be reversibly fed therebetween, and slidable means on each of said members to alternately engage them with said drive shaft to reversibly feed said ribbon, said alternation taking place each time the last layer of said ribbon is unwound from either of said members.

5. In a telegraph printer having a rack secured there'to; a movable type carriage, a ribbon feeding and reversing mechanism mounted on said carriage, a drive shaft secured to said mechanism, a pair of camming means mounted on said" drive shaft, gear and clutch means mounted on said drive shaft and engageable with said rack to drive said shaft as saidcarriage movesin a character spacing direction, a pair of rotatable spindles mounted in said mechanism, axially slidable means on'said spindles and rotatable therewith engageable alternately with said drive shaft, a pair of spools removably mounted on'said spindles and rotatable therewith, an ink ribbon mounted on said spools adapted to be reversibly fed therebetween, means coacting with one of said spools and one of said camming means to axially shift the slidable means on thespindle associated with said spool into engagement with said drive shaft and disengage the slidable means on the spindle associated with the other spool from said drive shaft whereby said'ribbon is' wound upon the operably engaged spool and p'ayed out from the disengaged spool, and means coacting'with said disengaged spool and said other cammingmeans when the'last layer of ribbon is payed out from said disengaged spool to alternate theen: gagement of said slidable means with said drive shaft whereby said ribbon feed isrevers'ed; g 6. A telegraph printer as defined in claim 5, wherein each of said means coacting with said spools and said camming means comprises a shiftable lever associated with one of said spools, spring means to shift said lever as the last layer of said ribbon is unwound from said spool, a cam follower operably connected with said lever to engage with one of said camming means when said lever is shifted, and a further means operably connected with said cam follower and each of said slidable means to engage one of said slidable means with said drive shaft and disengage said other slidable means from said drive shaft when said cam follower engages said camming means.

7. A telegraph printer as defined in claim 6, wherein each of said spools includes a core having an aperture therein, said ribbon being normally wound around said core to close said aperture; and said shiftable lever is assoits center on said mechanism, each end of said beam operably engaging one of said slidable means.

9. In a typewriter; a movable carriage; and an ink ribbon feeding and reversing device mounted on said carriage comprising a pair of vertical spindles, an ink ribbon mounted on said spindles and adapted to be reversibly fed therebetween, a drive shaft, an axially slidable member on each of said spindles to alternately engage them with said drive shaft to reversibly feed said ribbon, and means operable to drive said drive shaft as an incident to the movement of said carriage in a character spacing direction.

10. A device as defined in claim 9, wherein means are provided to alternate the engagement of said slidable members with said drive shaft each time the last layer of said ribbon is unwound from either of said spindles.

11. A device as defined in claim 9, wherein said drive shaft driving means includes a positive clutch, said clutch being disengaged during carriage return movement.

12. In a typewriter, a movable carriage, an axially fixed rotatable drive member mounted for rotation upon said carriage about an axis extending in the direction of movement of said carriage, a ribbon feeding mechanism supported on said carriage and operatively connectable to said drive member, a ribbon reversing mechanism supported on said carriage and operatively connectable to said drive member, and means, including a member fixed relative to the path of movement of said carriage and a gear mounted coaxial with said rotatable drive member and directly engaging said member fixed relative to the path of movement of said carriage, operative as an incident of movement of said carriage in a character spacing direction for imparting uni-directional rotation to said drive member to effect actuation of said mechanisms when operatively connected thereto.

13. A ribbon feeding device as defined in claim 1, further provided with automatic means coacting with said slidable means and said spools and adapted to be actuated by said rotatable driving member upon unwinding of the last layer of ribbon from a spool to engage said slidable movement receiving means with the rotatable driving member.

14. An ink ribbon feeding device for use on a type writer having a movable carriage, comprising: a frame adapted to be mounted on said movable carriage; a pair of spools rotatably mounted in said frame; slidable movement receiving means connected to said spools; means for imparting movement to said spools including a rotatable driving member mounted in axially fixed relation upon said frame and engageable with the movement receiving means of either of said spools, and a gear and clutch for operating said driving member as an incident to the movement of said carriage in a character spacing direcc9 tion to thereby impart movement to the movement receiving means of either of said spools.

15. An ink ribbon feeding and reversing device for use on a typewriter having a movable carriage, comprising a frame adapted to be mounted on said movable car riage, a pair of spindles journalled in said frame, an ink ribbon mounted on said spindles and adapted to be reversibly fed thcrebetween, a rotatable drive shaft journalled in and axially fixed relative to said frame, an axially slidable member on each of said spindles to alternatively engage them With said drive shaft to reversibly feed said ribbon, and means operable to drive said drive shaft as an incident to the movement of said carriage in a character spacing direction including an element adapted to be fixed to a non-movable part of the typewriter.

16. A device as set forth in claim 15, wherein said element adapted to be fixed to a non-movable part of the typewriter is a gear rack, and said means further includes a uni-directional gear drive connected with said drive shaft and adapted to be engaged with said gear rack when both the frame and gear rack are mounted on a typewriter, to drive said shaft only when the carriage moves in a character spacing direction.

17. In a typewriter, a movable carriage, an axially fixed drive member mounted for rotation upon said carriage about an axis extending in the direction of movement of said carriage, a reversible ribbon feeding mechanism supported on said carriage and operatively connectable to said drive member, a 'bbon reversing mechanism non-rotatably supported on said carriage relative to rotation of said drive member, operatively connected to said ribbon feed mechanism and including means movable into engagement with said axially fixed drive member to thereby render said reversing mechanism operable to reverse the connection of said ribbon feeding mechanism to said drive member, and means operative as an incident of movement of said carriage in a character spacing direction for imparting uni-directional rotation to said drive member to effect operation of said mechanisms when operatively connected and engaged therewith.

References Cited in the file of this patent UNITED STATES PATENTS 747,917 Hillard Dec. 22, 1903 1,096,010 Barr May 12, 1914 1,286,573 Poothorap Dec. 3, 1918 2,069,277 Sacerdote Feb. 2, 1937 2,257,553 Hept Sept. 30, 1941 2,531,872 Crumrine Nov. 28, 1950 

